Notes

[1] Yes, there are shortcomings in the methodology. What this really measures is how many blocks are written by the mkfs program. Even if you believe the figures, this only measures the initial overhead, but you can use the same technique to measure the overhead of storing (eg) lots of small files, or whatever is appropriate for your workload.
[2] Note the difference between ext2 and ext3/4 seems to be entirely down to the size of the journal, which is a kind of metadata overhead, but one that you can easily control.
[3] Needs three small patches to libguestfs to get these filesystems to work.
[4] This seems off the scale — needs further investigation.

About the author

I am Richard W.M. Jones, a computer programmer. I have strong opinions on how we write software, about Reason and the scientific method. Consequently I am an atheist [To nutcases: Please stop emailing me about this, I'm not interested in your views on it] By day I work for Red Hat on all things to do with virtualization.

My motto is "often wrong". I don't mind being wrong (I'm often wrong), and I don't mind changing my mind.

This blog is not affiliated or endorsed by Red Hat and all views are entirely my own.